U.S. patent application number 11/586270 was filed with the patent office on 2007-04-26 for self-cleaning intake screen.
Invention is credited to Russell M. III Berry, Russell M. IV Berry.
Application Number | 20070090041 11/586270 |
Document ID | / |
Family ID | 37984349 |
Filed Date | 2007-04-26 |
United States Patent
Application |
20070090041 |
Kind Code |
A1 |
Berry; Russell M. III ; et
al. |
April 26, 2007 |
Self-cleaning intake screen
Abstract
A self-cleaning screen that automatically cleans both the inside
and outside surfaces of the cylindrical screen using only the
rotation of the cylindrical screen itself. This self-cleaning
ability is accomplished by using a fixed brush on the exterior
surface of the screen, and a freely rotating brush on the interior
surface of the screen, where the freely rotating brush is driven by
the movement of the screen itself. A propeller driven by the
flowing water being filtered can be used to rotate the screen.
Inventors: |
Berry; Russell M. III; (Elk
Grove, CA) ; Berry; Russell M. IV; (Sacramento,
CA) |
Correspondence
Address: |
DLA PIPER RUDNICK GRAY CARY US, LLP
2000 UNIVERSITY AVENUE
E. PALO ALTO
CA
94303-2248
US
|
Family ID: |
37984349 |
Appl. No.: |
11/586270 |
Filed: |
October 24, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60730511 |
Oct 25, 2005 |
|
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|
Current U.S.
Class: |
210/396 ;
210/402 |
Current CPC
Class: |
B01D 33/073 20130101;
B01D 33/461 20130101; B01D 33/073 20130101; B01D 33/461
20130101 |
Class at
Publication: |
210/396 ;
210/402 |
International
Class: |
B01D 33/00 20060101
B01D033/00 |
Claims
1. A self-cleaning intake screen for filtering a flow of water,
comprising: a rotatable intake screen configured to filter material
from a flow of water, the intake screen having openings for passing
the flow of water; a propeller coupled to the intake screen for
rotating the intake screen as a flow of water passing the propeller
drives the propeller; and a first cleaning element operatively
coupled to the intake screen so as to remove the material from the
openings during rotation of the intake screen, wherein the first
cleaning element is rotatably coupled to the intake screen so that
rotation of the intake screen induces rotation of the first
cleaning element against the intake screen, so as to remove the
material from the openings when the intake screen is rotated;
wherein the openings are distributed across a cylindrical side
portion of the intake screen, and wherein the first cleaning
element extends longitudinally along an inner surface of the
cylindrical side portion.
2. The self-cleaning intake screen of claim 1 further comprising a
gear box coupled between the propeller and the intake screen.
3. The self-cleaning intake screen of claim 1 wherein the first
cleaning element is a brush having bristles configured to protrude
into the openings of the intake screen so as to remove the material
from the openings.
4. The self-cleaning intake screen of claim 3 wherein the brush is
rotatably coupled to the intake screen, and wherein rotation of the
intake screen engages one or more sides of the openings against one
or more of the bristles so as to rotate the brush, the rotation of
the brush moving others of the bristles into others of the
openings.
5. The self-cleaning intake screen of claim 1 further comprising a
second cleaning element proximate to an outer surface of the
cylindrical side portion, the second cleaning element configured to
further remove the material from the openings and the outer surface
when the intake screen is rotated.
6. The self-cleaning intake screen of claim 1 further comprising a
gear coupled to the first cleaning element and a complementary rack
coupled to the intake screen and the gear, wherein rotation of the
intake screen and the pinion rotates the gear so as to induce
rotation of the first cleaning element.
7. A self-cleaning intake screen for filtering a flow of water,
comprising: a manifold for passing a flow of water; a cylindrically
shaped screen defining a plurality of openings and rotatably
mounted to the manifold; a propeller disposed in the manifold and
coupled to the intake screen for rotating the intake screen as a
flow of water through the manifold drives the propeller; and a
first cleaning element rotatably mounted to the manifold and
engaged with the screen such that rotation of the screen causes
rotation of the cleaning element, wherein the first cleaning
element is a brush with bristles, and wherein the bristles
penetrate into the screen openings as the brush rotates; wherein
the screen includes: a plurality of spaced apart wires with the
openings defined between the wires; and a plurality of support
members extending along an interior surface of the screen; wherein
the bristles engage with the interior surface of the screen.
8. The self-cleaning intake screen of claim 7, further comprising a
second cleaning element mounted to the manifold and adjacent an
exterior surface of the screen, wherein the second cleaning element
slides along the exterior surface as the screen rotates.
9. The self-cleaning intake screen of claim 7 further comprising a
gear box coupled between the propeller and the screen.
10. The self-cleaning intake screen of claim 7, wherein the
manifold includes a cylindrically shaped member about which the
screen rotates, and wherein the first cleaning element is mounted
between the cylindrically shaped member and the screen.
11. The self-cleaning intake screen of claim 7, wherein the first
cleaning element includes a shaft.
12. The self-cleaning intake screen of claim 11, wherein the
bristles extend from the shaft in a spiral manner.
13. The self-cleaning intake screen of claim 11, further comprising
a tray mounted to the manifold, wherein the first cleaning element
is rotatably disposed in the tray.
14. A self-cleaning intake screen for filtering a flow of water,
comprising: a cylindrically shaped manifold; a cylindrically shaped
screen disposed around the manifold in a rotatable manner relative
to the manifold, the screen defining a plurality of openings; a
propeller disposed in the manifold and coupled to the intake screen
for rotating the intake screen around the manifold as a flow of
water through the manifold drives the propeller; and a first
cleaning element rotatably mounted to the manifold and disposed
between the manifold and the screen, wherein the cleaning element
is engaged with an interior surface of the screen such that
rotation of the screen causes rotation of the cleaning element.
15. The self-cleaning intake screen of claim 14, wherein the
cleaning element includes a shaft and a plurality of bristles
extending from the shaft, and wherein the bristles extend into the
screen openings as the screen rotates.
16. The self-cleaning intake screen of claim 15, further comprising
a second cleaning element mounted to the manifold and adjacent an
exterior surface of the screen, wherein the second cleaning element
slides along an exterior surface of the screen as the screen
rotates.
17. The self-cleaning intake screen of claim 15, further comprising
a tray mounted to the manifold, wherein the cleaning element is
rotatably disposed in the tray.
18. The self-cleaning intake screen of claim 14 further comprising
a gear box coupled between the propeller and the screen.
Description
[0001] This application claims the benefit of U.S. Provisional
Application No. 60/730,511, filed Oct. 25, 2005, and entitled
Self-Cleaning Intake Screen.
FIELD OF THE INVENTION
[0002] This invention relates to intake screens to exclude material
from entering a water inlet, and is particularly directed to an
improved self-cleaning intake screen.
BACKGROUND OF THE INVENTION
[0003] Self-cleaning intake screens are well known in the art. The
earliest of such devices simply employed some mechanism to cause
the screen, generally cylindrical in shape, to rotate within the
stream or waterway. A water vacuum is generated inside the
cylindrical screen, drawing water through the screen for
filtration. As the screen rotates, any debris trapped on its
upstream side would be washed away as it turns downstream. More
sophisticated devices employ some sort of backwash system which,
either continually or at periodic intervals, spray a high pressure
jet of water or air against the screen in an attempt to blow debris
off of and away from the outside of the screen. However, most
self-cleaning intake screen designs are complicated and/or do not
effectively keep the screen free from debris.
[0004] More recently, brushes and scrapers have been added to the
outside of cylindrical screens, to scrape off debris and silt from
the outer surface of the screen as the screen rotates, so that
water flow through the screen to the interior of the screen is not
unnecessarily impeded. However, for many applications, the interior
of the screen still experiences an intolerable build up of debris
and silt. For example, one application involves a screen made of
wedge wires, which are thick wire strands that extend
circumferentially around a support structure. The support structure
includes longitudinally extending support members that are attached
to the inside surface of the wedge wire screen, and are spaced one
or several inches apart. It has been found that an external brush
sweeping across the outer surface of the wedge wire screen fails to
adequately clean the inside surface of the wedge wire and the
support members, as well as possibly the laterally facing surfaces
of the wedge wires. Spacing the support members further apart can
reduce silt buildup, but then the screen no longer has the desired
structural integrity, and the cylinder can lose its roundness as
the wedge wire tends to lie flat between the support members.
[0005] It is also known to place a spirally oriented, motorized
cleaning brush on the inside surface of a rotating cylindrically
shaped screen, where the brush rotates in the opposite direction as
the moving direction of the screen. However, such motorized
cleaning brushes will not work with wedge wire type screens such as
the one described above, because the brush will continually
encounter the support members, which are not flush with the inside
surface of the wedge wire screen. Thus, any brushes designed to
clear the support members will not adequately clean the interior
and lateral surfaces of the wedge wire. Moreover, it is expensive
and difficult to include a separate motor, inside the cylindrical
screen, to operate the rotating brush.
[0006] There is a need for an intake screen that reliably and
effectively cleans itself, even its interior surfaces, without
adding the complexity of additional motors.
SUMMARY OF THE INVENTION
[0007] The present invention solves the aforementioned problems by
providing a self-cleaning intake screen.
[0008] A self-cleaning intake screen comprises a rotatable intake
screen configured to filter material from a flow of water, wherein
the intake screen has openings for passing the flow of water. The
screen further comprises a propeller coupled to the intake screen
for rotating the intake screen as a flow of water passing the
propeller drives the propeller. And finally, the screen comprises a
first cleaning element operatively coupled to the intake screen so
as to remove the material from the openings during rotation of the
intake screen, wherein the first cleaning element is rotatably
coupled to the intake screen so that rotation of the intake screen
induces rotation of the first cleaning element against the intake
screen, so as to remove the material from the openings when the
intake screen is rotated, and wherein the openings are distributed
across a cylindrical side portion of the intake screen, and wherein
the first cleaning element extends longitudinally along an inner
surface of the cylindrical side portion.
[0009] In another aspect of the present invention, a self-cleaning
intake screen comprises a manifold, a cylindrically shaped screen
defining a plurality of openings and rotatably mounted to the
manifold, and a propeller disposed in the manifold and coupled to
the intake screen for rotating the intake screen as a flow of water
through the manifold drives the propeller. The screen further
comprises a first cleaning element rotatably mounted to the
manifold and engaged with the screen such that rotation of the
screen causes rotation of the cleaning element, wherein the first
cleaning element is a brush with bristles, and wherein the bristles
penetrate into the screen openings as the brush rotates. Within
this embodiment, the screen includes a plurality of spaced apart
wires with the openings defined between the wires, and a plurality
of support members extending along an interior surface of the
screen, wherein the bristles engage with the interior surface of
the screen.
[0010] In yet one more aspect of the present invention, a
self-cleaning intake screen comprises a cylindrically shaped
manifold, a cylindrically shaped screen disposed around the
manifold in a rotatable manner relative to the manifold, wherein
the screen comprises a plurality of openings, and a propeller
disposed in the manifold and coupled to the intake screen for
rotating the intake screen around the manifold as a flow of water
through the manifold drives the propeller. The screen further
comprises a first cleaning element rotatably mounted to the
manifold and disposed between the manifold and the screen, wherein
the cleaning element is engaged with an interior surface of the
screen such that rotation of the screen causes rotation of the
cleaning element.
[0011] Other aspects and advantages of the invention will become
apparent from the following detailed description taken in
conjunction with the accompanying drawings which illustrate, by way
of example, the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] For a better understanding of the invention, reference
should be made to the following detailed description taken in
conjunction with the accompanying drawings, in which:
[0013] FIG. 1 is a cross-sectional side view of a self-cleaning
intake screen.
[0014] FIG. 2 is a cross-sectional end view of the self-cleaning
intake screen of the present invention.
[0015] FIG. 3 is a perspective view of the suction manifold of a
self-cleaning intake screen.
[0016] FIGS. 4 and 5 are perspective views of the wedge wire
surface and external brush of the self-cleaning intake screen of
the present invention.
[0017] FIG. 6 is a perspective view of the interior of the
self-cleaning intake screen of the present invention.
[0018] FIG. 7 is a top view of the internal brush of the
self-cleaning intake screen of the present invention.
[0019] FIG. 8 is a perspective view of the suction manifold and
internal brush of the self-cleaning intake screen of the present
invention.
[0020] FIG. 9 is a perspective view of the wedge wire surface,
external brush, and protruding bristles of the interior brush, of
the self-cleaning intake screen of the present invention.
[0021] FIG. 10 is a cross-sectional side view of an alternate
embodiment of a self-cleaning intake screen.
[0022] FIG. 11 is an end view of the alternate embodiment of a
self-cleaning intake screen.
[0023] FIG. 12 is a partially broken away view of a self-cleaning
intake screen according to another alternate embodiment.
[0024] FIG. 13 is an end view of a self-cleaning intake screen
according to the alternate embodiment of FIG. 12.
[0025] Like reference numerals refer to corresponding parts
throughout the drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0026] The present invention is a self-cleaning intake screen
assembly 1, as shown in FIGS. 1 and 2. The assembly 1 includes a
cylindrical shaped screen 10 rotatably mounted to a suction
manifold 12, an external fixed brush 14, and an internal rotating
brush 16. The entire assembly is designed to be submerged under
water, where suction applied inside the suction manifold 12 draws
water through the cylindrical screen 10 and the suction manifold
12, where the screen 10 filters out contaminants from the
water.
[0027] Suction manifold 12 is cylindrically shaped, having an open
end 18, a closed end 19, and a cylindrically shaped sidewall 20. A
pump manifold 22 (attached to the intake side of a pump which is
not shown) is connected to the suction manifold 12, for drawing
water through the screen 10 and the suction manifold 12 and
eventually to the pump (not shown). The suction manifold 12
includes a plurality of apertures 24 formed in its cylindrical
sidewall 20 through which water will flow, as better shown in FIG.
3. The apertures 24 are evenly spaced to ensure a more even flow of
water though various portions of screen 10. Motor 26 is mounted to
the closed end 20 of suction manifold 12, and includes a rotating
drive shaft 28 that extends through the suction manifold closed end
20.
[0028] Screen 10 includes a first end plate 30 connected to the
motor drive shaft 28, a second end plate 32 with a plurality of
rollers 34 attached thereto, and a sidewall 36 formed by wedge wire
38 extending circumferentially around a center of the screen 10 and
supported by support members 40 that longitudinally extend between
the first and second end plates 30/32, as best shown in FIGS. 1 and
4-6. Wires 38 are separated from each other to form small openings
39 therebetween through which the water flows (as best seen in FIG.
9). Screen 10 is disposed around suction manifold 12, and is
rotatably supported at one end by the motor drive shaft 28 and the
other end by the rollers 34 (which engage the suction manifold
cylindrical sidewall 20).
[0029] The external brush 14 includes bristles 42 supported by a
support bracket 44, as best illustrated in FIGS. 2-5. Bristles 42
sweep across the outer surface of the screen sidewall 36 (wedge
wire 38) as the screen 10 rotates relative to the suction manifold
12.
[0030] The internal brush 16 includes a shaft 46 rotatably mounted
to the suction manifold 12 via brackets 48, and bristles 50
extending from the shaft 46 preferably, but not necessarily, in a
spiral fashion, as best illustrated in FIGS. 2 and 7. Brackets 48
can be incorporated as end plates of a unitary trough or tray 52
for integrity, as best shown in FIGS. 3 and 8. The brush 16 is
positioned to engage with the interior surface of screen sidewall
36 (wedge wire 38 and support members 40).
[0031] In operation, motor 26 rotates screen 10 relative to suction
manifold 12. As screen 10 rotates, bristles 42 of fixed external
brush 14 slide across the outer surface of sidewall 20 (i.e. outer
surface of wedge wire 38) dislodging material such as debris and
silt therefrom. Also, as screen 10 rotates, the support members 40
act as gear teeth by engaging with and rotating internal brush 16.
As internal brush 16 rotates, its bristles 50 engage with support
members 40 and inner and side surfaces of wedge wire 38, even
poking through the wedge wire 38 as illustrated in FIG. 9. This
engagement wipes and dislodges debris and silt from the support
members 40 and the inner/side surfaces of wedge wire 38. By
rotating with the passing support members 40 (in a passive manner),
the internal brush 16 effectively cleans the interior of the screen
10 in a manner that the external fixed brush 14 can not. Also, by
passively rotating internal brush 16 using the rotation of screen
sidewall 36, a second motor and/or complicated gearing is avoided.
Thus, the rotation of screen 10 operates both brushes (one fixed
and one rotating) without the need for any additional motors or
moving parts.
[0032] The preferred embodiment of the present invention includes a
pair of screen assemblies 1 mounted to a single pump manifold.
Hoist mechanisms can be used to lower and raise the intake screen
assembly into a waterway for use. Components with dissimilar metals
are electrically isolated to prevent electrolysis.
[0033] One of skill will realize that the present invention is not
limited to the embodiment described above. Rather, alternate
embodiments exist. FIGS. 10-11 illustrate one such alternate
embodiment. The embodiment of FIGS. 10-11 highlights the fact that
the present invention is not limited to configurations in which the
brush 16 is rotated only by its bristles 50. Rather, here, the
brush 16 has a gear 100 that is aligned with a complementary rack
102 that is positioned along the inner surface 104 of the screen
10, and whose teeth 104 are configured to interlock with the teeth
of the gear 100 in a rack-and-pinion type arrangement. Accordingly,
rotation of the screen 10 and rack 102 also induces rotation of the
gear 100 and thus the brush 16. In this embodiment, the bristles 50
need not frictionally engage against the screen 10, as the brush 16
is turned by the rack 102 and gear 100. This reduces wear on the
bristles 50 and extends the useful life of the brush 16.
[0034] Another embodiment of the present invention is illustrated
in FIGS. 12-13. Within such embodiment, motor 26 and shaft 28 of
the previous embodiments are replaced with propeller 200, drive
shaft 202, drive shaft coupling 204, gear box 206 (e.g. 1200:1 gear
ratio), propeller bearing and support 208, gear box drive plate
210, seal 212 between the suction pipe (via flange 214) and
rotating cylinder 10, and pick loop 216 (for hoisting the assembly
into place). In this embodiment, water flowing through the suction
manifold 12 drives propeller 200, which in turn rotates the drive
shaft 202 and the coupling 204 to drive the gear box 206. The gear
box 206 sufficiently down-gears the rotational movement of the
drive shaft, so rotational force imparted on the screen cylinder
end plate 30 via the gear box drive plate 210 is sufficient to
rotate the screen 10 against all frictional forces (including those
imparted by brushes 14 and 16). For example, using a 1200 to 1
gearbox, and a flow rate of 2000 gallons per minute, a rotation of
0.25 to 0.50 rpm of the cylinder 10 has been achieved.
[0035] The embodiment illustrated in FIGS. 12-13 provides inherent
advantages over the previously described embodiments. For example,
because this embodiment utilizes the pressure of flowing water to
drive propeller 200, a motor dedicated to rotating the screen is
not needed. Moreover, because this embodiment is a completely
passive system, no underwater power is needed. As such, this
embodiment reduces the cost and complexity, while enhancing
reliability.
[0036] It is to be understood that the present invention is not
limited to the embodiments described above and illustrated herein,
but encompasses any and all variations falling within the scope of
the appended claims. For example, the internal brush 16 is simply
coupled to the screen 10 so that rotation of the screen 10 also
moves the internal brush 16 against the screen 10. The brush 16
need not be moved specifically by its bristles 50, but instead can
be moved by rotation of the screen 10 in any appropriate manner.
The use of passively rotating internal brush 16 need not be used in
conjunction with a suction manifold for applications where even
water flow through the screen 10 is not needed. While internal and
external brushes 14/16 are shown as mounted in an opposing fashion
(on either side of the screen sidewall 36), such an opposing
relationship is unnecessary. The screen sidewall 10 need not be
formed of wedge wire 38 and support members 40, but can be formed
of any mesh or other known screen materials (i.e. thin wires to
thick wires that resemble rigid bars) that provide the desired
filtration of water flowing therethrough and can engage and rotate
the internal brush 16. The internal and external brushes 14/16 need
not be brushes with protruding bristles 50/42, but can be any
cleaning element capable of removing material from the intake
screen 10, such as scrubbing pads or the like. In particular, the
internal brush 16 can be a cleaning element having any
configuration that allows it to engage against the intake screen 10
so as to induce rotation. The flow of water can be reversed from
that shown, in which case the support members 40 are preferably on
the outside of the screen as is the rotating brush 16, and the
fixed brush 14 is mounted inside the screen. The spacing and sizes
of holes 24 can be varied to create more even flow. And, brush 16
can be freely disposed in tray 52, without the ends thereof being
rotatably attached to the tray ends. Lastly, the propeller 200 need
not necessarily be coupled to the screen via the drive shaft 202,
coupling 204 and gear box 206, but rather can be directly or
indirectly coupled to the screen in any manner that imparts
sufficient torque on the screen so that the screen rotates at the
desired speed given the expectant flow rates of water.
[0037] Thus, the foregoing description of specific embodiments of
the present invention are presented for purposes of illustration
and description. They are not intended to be exhaustive or to limit
the invention to the precise forms disclosed, obviously many
modifications and variations are possible in view of the above
teachings. The embodiments were chosen and described in order to
best explain the principles of the invention and its practical
applications, to thereby enable others skilled in the art to best
utilize the invention and various embodiments with various
modifications as are suited to the particular use contemplated. Any
element or combination from one embodiment can be incorporated in
any other embodiment or combination.
* * * * *